1. Field
This document relates to an apparatus and method for controlling a camera according to temperature.
2. Related Art
In recent years, as the Digital Video Recorder (DVR) is commercialized, a number of monitoring cameras are installed at places requiring security as shown in FIG. 1. Monitoring images are captured by the cameras, and then transmitted to and recorded into the DVR at a remote place.
The monitoring cameras are generally installed at indoor or outdoor open places due to sensitive problems such as privacy. In particular, cameras operating outdoors are exposed to external temperature variation and thus have their operation and performance influenced by such temperature variation. This temperature variation particularly has a great influence on an optical system.
In this case, the length of a lens barrel for fixing or supporting a zoom lens, a focusing lens, etc., the position of lenses, the refractive index of the lenses, and so on are changed according to temperature. For example, as shown in FIG. 2, when temperature is lowed, the length of the lens barrel can be shortened. In the state where a desired subject is focused in manual focus mode, the focused position is changed as temperature is changed, so the desired subject may not be focused on.
Further, when temperature within a camera abruptly changes or is in an ultra-low temperature state, the camera may not perform a normal photographing operation. For example, when an internal temperature of a camera is in an ultra-low temperature state of −40 degrees Celsius, the performance of respective electronic components, equipments, and optical elements is degraded, hindering a normal photographing operation.